Method and apparatus for disposing of human waste in a vehicle

ABSTRACT

A method and apparatus for disposing of liquid and organic waste in a vehicle wherein the waste is periodically moved by a pump from a holding tank to a heating chamber which utilizes the heat of the vehicle exhaust. In the heating chamber, all bacteria in the waste are vaporized and destroyed by the heat of the vehicle exhaust which converts the waste to a product that is principally steam and which can be harmlessly passed through the remainder of the exhaust system. The pump which conveys the waste from the holding tank to the heating chamber operates only when a combination of two circumstances exist, namely, only when the vehicle is travelling at a speed above a predetermined speed and when the temperature in the heating chamber is above a predetermined temperature. Limiting the operation of the apparatus to those times when the vehicle is moving is also utilized to prevent clogging of the filtered inlet of the pipe which extends into the holding tank so as to employ the agitation of the liquid therein to wash the pipe inlet.

United States Patent 1191 Sargent June 26, 1973 METHOD AND APPARATUS FORDISPOSING OF HUMAN WASTE IN A [57] ABSTRACT VEHICLE A method andapparatus for disposing of liquid and or- [75] Inventor: Charles L.Sargent, Ypsilanti, Mich. garlic waste in a vehicle wherein waste iscally moved by a pump from a holding tank to a heating AS51811:Thermason Corporation, Ann Arbor, chamber which utilizes the heat of thevehicle exhaust. Mlch- In the heating chamber, all bacteria in the wasteare va- [22] Filed; June 24, 1971 porized and destroyed by the heat ofthe vehicle exhaust which converts the waste to a product that is PP N05156,403 principally steam and which can be harmlessly passed through theremainder of the exhaust system. The 52 U.S. c1. 4/114, 4/131 P whichConveys the Waste fmm the 8 h 51 11111. Cl. B60r 15/04 9 the heahhgchamber Only when 8 [58] Field of Search 4/8, 114, 131 l ofcll'cufnstances eXISI, namely, only when the vehicle is travellmg at aspeed above a predetermined [56] References Cited Zpeed 1nd when tilettemperdature in the helaiin gtichatrlrlier is a ove a pre e ermineempera ure. m1 ng e UNITED STTES PATENTS operation of the apparatus tothose times when the veg; i s i 4/ hicle is moving is also utilized toprevent clogging of the 0 man e a filtered inlet of the pipe whichextends into the holding 1,818,586 8/1931 Schumacher 4/114 X tank so asto p y the agitation of the liquid therein Primary ExaminerKenneth W.Sprague to wash the plpe mlet' Attorney-Finn G. Olsen et a1. 12 Claims,6 Drawing Figures as 1 I 32 A i 22 I i 1 i I 1 l 1 I 11 24 {E I 3e 1 i A|l PATENIEDJUNZBIBH SHEEI 1 0F 2 (ONTROL BOX INVENTOR w CHARLES LSARGENTFIG?) avgz w ATTORNEYS PAlENlEuJunzems 3740.773

INVENTOR CHARLES L. SARGENT 30 BY Mg/w ATTORNQYS METHOD AND APPARATUSFOR DISPOSING OF HUMAN WASTE IN A VEHICLE BACKGROUND OF THE INVENTIONThis invention relates generally to the field of waste disposal and moreparticularly to a method and apparatus for disposing of human waste suchas toilet waste and wash water waste from a vehicle of the type that ispropelled by a fuel burning engine.

The invention is particularly applicable to recreational vehicles havinginternal combustion engines although it is to be understood that theinvention has broader applications and may be used in other vehiclessuch as buses, boats or airplanes. The invention is also useful with anyvehicle having a fuel burning engine of the type provided with anexhaust pipe, such as diesel engines and turbines.

Recreational vehicles, trailers, buses, boats and airplanes are commonlyprovided with toilets and lavatories for use by human occupants of thevehicle. In the usual case, the toilet has an outlet which leads to aholding tank for the waste, and in some cases the lava tory has anoutlet which leads to the same holding tank. In the past, it has beennecessary to periodically manually empty the holding tank, and this isnot only an inconvenience but an unpleasant task. This is particularlytrue because discharge facilities for the holding tanks are not readilyavailable at convenient locations. Even when such a location is found,it is necessary to connect a hose or carry the waste in buckets from theholding tank to a discharge opening of a sewer leading to a sewagetreatment plant.

U.S. Pat. No. Re. 26,891 suggests employing the waste heat from thevehicle engine for vaporizing liquid waste. However, in the systemdisclosed in the aforementioned patent, the waste is injected into adrum which surrounds the exhaust pipe and the necessary temperatures forkilling bacteria and odor producing compounds in the waste cannot bereached in a system of this type. US. Pat. No. 2,658,202 shows a vehicledisposal system for vehicles wherein the incineration step isaccomplished in an externally heated coil having a discharge valve whichcan be opened only when the vehicle is moving. It can readily beappreciated that this is quite different from the present inventionwherein the vaporizing and sanitizing of the waste takes placeconcurrently with expelling of the waste into the atmosphere since thewaste is vaporized directly in the vehi-' cle exhaust. It is an objectof the present invention, therefore, to provide an improved method andapparatus for disposing of liquid and organic waste in a vehicle bydischarging the waste directly into the vehicle exhaust only duringmovement of the vehicle.

SUMMARY OF THE INVENTION porize the liquid waste and heat the particlesto a temperature sufficient to kill all bacteria therein so as toeffectively sanitize this material. A speed sensing device on thevehicle is connected to the pump so that the necessary electrical signalfor actuating the pump is provided only when the vehicle is traveling ata speed that is above a selected speed. In order for the pump tooperate, it is also necessary that the pump receive a signal from atemperature sensing probe which extends into the heating chamber. As aresult, the pump will operate to pump waste from the holding tank to theheating chamber only when the temperature in the heating chamber issufficient to insure the destruction of all bacteria and odor producingagents in the waste. In addition, to positively preclude the presence ofany residual odors from the waste in the vicinity of the vehicle, theconnection of the speed sensing device to the pump insures that wastesanitizing will occur only when the vehicle is moving at a speed above apredetermined low speed. Structure in the heating chamber defines atortuous path through which the hot engine exhaust gases must flow fromthe inlet to the outlet of the chamber, the temperature sensing probe islocated near the outlet for the chamber and the waste is discharged intothe chamber adjacent the inlet to thereby assure subjection of the wasteto gases which are always hotter than the temperature of the gasessensed by the probe. To insure against clogging of the conduit whichextends between the holding tank and the heating chamber, a filter isprovided on the conduit within the holding tank at a location such thatagitation of the fluid within the tank caused by motion of the vehiclewill act to clean the filter. Limiting of intake into the filter to onlythose times when the vehicle is moving insures continuous cleaning ofthe filter. Thus, the method and apparatus of this invention providesfor the complete disposal of liquid and organic waste from the holdingtank without any possibility of residual odors around the vehicle.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of theapparatus of this invention shown in assembly relation with a vehicle,only portions of which are illustrated;

FIG. 2 is a vertical sectional view of the holding tank in the apparatusof this invention showing the inlet and outlet conduits therefor;

FIG. 3 is a longitudinal sectional view of the waste sanitizer unit inthe apparatus of this invention as seen from substantially the line 3-3of FIG. 4;

FIG. 4 is an end view of the sanitizer unit in the apparatus of thisinvention;

FIG. 5 is a wiring diagram showing the assembly of the pump and thecontrol elements therefor in the apparatus of this invention; and I FIG.6 is a view of the operating control panel for the apparatus of thisinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Before explaining the presentinvention in detail, it is to be understood that the invention is notlimited in its application to the details of construction andarrangement of parts illustrated in the accompanying drawings, since theinvention is capable of other embodiments and of being practiced orcarried out in various ways. Also, it is to be understood that thephraseology or terminology employed herein is for the purpose ofdescription and not of limitation.

With reference to the drawing, the apparatus of this invention,indicated generally at 10, is illustrated in FIG. 1 in assembly relationwith a vehicle 12 having an engine 14, of internal combustion type,having an exhaust pipe 16. The apparatus includes a holding tank 18which is connected by an inlet pipe 20 with a toilet, and in some casesa lavatory, on the vehicle 12, so that the holding tank 18 receivesliquid and organic toilet wastes.

The apparatus 10 also includes a sanitizer unit 22 which, as shown inFIGS. 3 and 4, consists of a housing 24 having end walls 26 and 28. Theunit 22 is interposed in the exhaust pipe 16 so that the unit 22 has anoutlet pipe 30 mounted in the end wall 26 and an inlet pipe 32 mountedin the end wall 28. The interior of the housing 24 constitutes a heatingchamber 34 which is configured so that the hot exhaust gases travelingthrough the housing 24 must follow a tortuous path indicated by thearrows 36 in FIG. 3. A waste supply conduit 38 terminates in a dischargeend 40 which projects into the heating chamber 34 at a position close tothe inlet pipe 32. A temperature sensing probe 42 in the form of athermocouple, is mounted at 44 at a position close to the outlet pipe30. As a result, since the exhaust gases inevitably cool to some extentduring travel from the inlet pipe 32 to the outlet pipe 30, the sensingprobe 42 will always sense a temperature which is cooler than thetemperature in the heating chamber 34 adjacent to the discharge end 40of the conduit 38 where the waste to be sanitized is discharged. Thisarrangement insures that the temperature within the chamber 34 willalways be at a high enough temperature to accomplish the necessary wastesanitizing.

The inlet conduit 38 for the unit 22 is connected to a pump 46 (FIG. 1)which is driven by an electric motor 48. The pump 46 is also connectedto a conduit 50 connected to the holding tank 18 and provided on itsinlet end with a tubular filter 52 which is positioned within theholding tank 18 as shown at FIG. 2. The filter 52 projects horizontallyinto the tank 18 at a position above the bottom wall 54 of the tank 18,which is also provided with a cleanout plug 56, so that when the vehicle12 is in motion the agitation of the fluid within the tank 18 willcontinuously wash across the filter 52 to prevent it from becomingclogged. Thus, when the pump 46 is operating. liquid waste containingsmall particles of organic waste is moved by the pump 46 through theconduits 50 and'38 for discharge into the unit 22. In the unit 22, thewaste is subjected to the hot exhaust gases which create a turbulentsuperheated steam bath in the chamber 34 which vaporizes the liquidwaste and totally destroys all of the bacteria within the waste.

The pump motor 48 is connected by conductors 58 and 60 to a control box62 and the vehicle battery 64, as shown in FIG. 5. The control box 62 isalso connected by a conductor 66 to a speed sensing unit 68 and byconductors 70 to the temperature sensing probe 42. Still otherconductors 72 connect the battery 64 to the control box 62. The speedsensing device 68 is a conventional speed switch which is connected tothe conventional speedometer cable for the vehicle 12 at thetransmission. Conventional structure within the control box 62 providesfor the transmission of a turnon electrical signal to the motor 48 onlywhen the speed sensing device 68 senses a speed of the vehicle 12 abovea predetermined speed, for example a speed of 30 miles per hour or aspeed range of 2540 m.p.h., and when the temperature sensing probe 42indicates a temperature in the heating chamber 34 above a predeterminedtemperature, for example, 750 F. Thus, only when both of thesetemperature and speed conditions exist will the motor 48 drive the pump46. As a result, destruction of bacteria and objectionable odors in thewaste in the heating chamber 34 is assured. Since the pump 46 canoperate only when the vehicle 12 is traveling above a predeterminedspeed for which the speed switch 68 is set, any possibility of residualodors from the burning of the waste in the burner 22 remaining in thevicinity of the vehicle 12 is eliminated. In addition, since the pump 46can operate only when the vehicle is in motion, possibility of cloggingof the filter 52 by solid matter in the waste within the holding tank 18is likewise eliminated because fluid is being drawn through the filter52 only when the vehicle is in motion and the vehicle motion producesagitation of the fluid in the holding tank 18 which in turn washes andcleanses the filter 52 so as to maintain it in an unclogged condition.

The vehicle 12 is equipped with an operating panel 74 (FIG. 6)positioned in a convenient location for the vehicle operator andconsisting of an on-off switch 80, a ready light 82 and a reaction light84. To start the apparatus 10, the operator first turns the switch tothe on position which provides for energizing of the ready light 82.When the speed of the vehicle reaches a speed above the speed or speedrange for which the switch 68 is set, the sensing speed unit 68 willprovide an actuating electrical signal to the pump motor 48 and at thisspeed, assuming the engine 14 is under load, the temperature in theheating chamber 34 will also be above the preset temperature so that theprobe 42 will likewise provide the necessary electrical signal for theoperation of the motor 48. The pump 46 will then operate to deliverliquid and organic waste to the sanitizer unit 22 from the holding tank18 and will operate continuously in this manner until either the vehiclespeed falls below the preset speed for the temperature in the chamber 34falls below the preset temperature. The latter condition would likelyhappen only when the vehicle 12 is traveling downhill so that there isno load on the engine 14. During operation of the pump 46, the reactionlight 84 on the panel 74 will glow to indicate to the vehicle operatorthat the apparatus 10 is operating to dispose of waste. When the vehicleslows down to a speed below the speed for which the sensing unit 68 isset, the pump 46 will stop and the light 84 will go out.

It can thus be'seen that the apparatus 10 of this invention operatescontinuously while the vehicle 12 is in motion to destroy waste from theholding tank 18 and when the vehicle 12 is traveling at a slow rate ofspeed or is at rest, the waste is maintained in the holding tank 18 forfuture disposal. As a result, disposal of the waste is accomplished at atime when there is no danger that any residual odors will have anadverseeffect on the occupants ofthe vehicle 12. Furthermore, when theapparatus 10 is operating to dispose of waste, a complete destruction ofall bacteria and all but residual odors is insured.

It is claimed:

1. In a vehicle having an engine provided with an exhaust system,apparatus for disposing of liquid and organic waste comprising a holdingtank for said waste, means forming a heating chamber in said exhaustsystem for vaporizing and sanitizing said waste, vehicle speed sensingmeans, and pump means operatively associated with said speed sensingmeans and connected to said holding tank and said heating chamber forcon veying waste from said tank to said chamber only when said sensingmeans senses a speed of said vehicle above a predetermined speed.

2. Apparatus according to claim 1 further including means capable ofsensing the temperature in said chamber and operatively associated withsaid pump means providing for operation of said pump means only when thetemperature in said chamber is above a predetermined temperature.

3. Apparatus according to claim 2 wherein said temperature sensing meanscomprises probe means extending into said chamber.

4. Apparatus according to claim 1 wherein said pump means is anelectrically driven pump and said speed sensing means operates toprovide an electrical operating signal to said pump.

5. Apparatus according to claim 1 wherein said heating chamber comprisesa housing having a pair of ends, an inlet for said housing in one ofsaid ends and an outlet for said housing in the other one of said ends,and means in said housing defining a tortuous path through which hotgases must flow from said inlet to said outlet.

6. Apparatus according to claim 5, wherein said pump means is connectedto said chamber by a conduit means which terminates in said chamber at aposition in said path closer to said inlet than to said outlet.

7. Apparatus according to claim 6 wherein said pump means is connectedto said tank by pipe means that is in fluid communication with saidtank, and filter means for said pipe means disposed in said tank at aposition above the lower wall thereof so that agitation of liquid insaid tank caused by motion of said vehicle will act to clean said filtermeans.

8. Apparatus according to claim 5 further including temperature sensingmeans connected to said pump means providing for operation thereof onlywhen the temperature in said chamber is above a predeterminedtemperature, said temperature sensing means extending into said chamberat a position in said path closer to said outlet thereof than the inlet.

9. In a vehicle, apparatus for disposing of liquid and organic wastecomprising a waste holding tank having a bottom wall, sanitizer meansfor vaporizing and sanitizing said waste, vehicle speed sensing means,pump means operatively associated with said speed sensing means forconveying waste from said tank to said sanitizer means only when saidsensing means senses movement of said vehicle, and conduit meansconnecting said pump to said holding tank, said conduit meansterminating in a filter member disposed in said tank at a positionspaced above said bottom wall so that agitation of liquid in said tankwill wash said filter member.

10. Apparatus according to claim 9 wherein said filter member is tubularand is in a generally horizontal position in said tank.

11. A method of disposing of liquid and organic waste in a vehiclehaving an engine, said method comprising the steps of:

a. collecting said waste at one location on said vehicle;

b. utilizing the heat from said engine to sanitize and vaporize saidwaste at another location on said vehicle; and

c. continuously moving said waste from said one to said another locationonly when said vehicle is moving at a speed above a predetermined speedand when the temperature at said other location is above a predeterminedtemperature, and retaining said waste in said one location when saidvehicle is stationary or moving at a speed below said predeterminedspeed.

12. In a vehicle having an engine provided with an exhaust system intowhich waste heated gases from the engine are discharged, apparatus fordisposing of liquid and organic waste comprising a holding tank forreceiving said liquid and organic waste, conduit means in communicationwith said holding tank and said exhaust system, vehicle speed sensingmeans, temperature sensing means for measuring a temperature conditionassociated with the operation of said engine, and pump means operativelyassociated with said speed sensing means and said temperature sensingmeans and located in said conduit means for conveying waste from saidholding tank to heated gases in said exhaust system only when said speedand temperature sensing means sense speed and temperature conditionsabove predetermined minimum values.

1. In a vehicle having an engine provided with an exhaust system,apparatus for disposing of liquid and organic waste comprising a holdingtank for said waste, means forming a heating chamber in said exhaustsystem for vaporizing and sanitizing said waste, vehicle speed sensingmeans, and pump means operatively associated with said speed sensingmeans and connected to said holding tank and said heating chamber forconveying waste from said tank to said chamber only when said sensingmeans senses a speed of said vehicle above a predetermined speed. 2.Apparatus according to claim 1 further including means capable ofsensing the temperature in said chamber and operatively associated withsaid pump means pRoviding for operation of said pump means only when thetemperature in said chamber is above a predetermined temperature. 3.Apparatus according to claim 2 wherein said temperature sensing meanscomprises probe means extending into said chamber.
 4. Apparatusaccording to claim 1 wherein said pump means is an electrically drivenpump and said speed sensing means operates to provide an electricaloperating signal to said pump.
 5. Apparatus according to claim 1 whereinsaid heating chamber comprises a housing having a pair of ends, an inletfor said housing in one of said ends and an outlet for said housing inthe other one of said ends, and means in said housing defining atortuous path through which hot gases must flow from said inlet to saidoutlet.
 6. Apparatus according to claim 5, wherein said pump means isconnected to said chamber by a conduit means which terminates in saidchamber at a position in said path closer to said inlet than to saidoutlet.
 7. Apparatus according to claim 6 wherein said pump means isconnected to said tank by pipe means that is in fluid communication withsaid tank, and filter means for said pipe means disposed in said tank ata position above the lower wall thereof so that agitation of liquid insaid tank caused by motion of said vehicle will act to clean said filtermeans.
 8. Apparatus according to claim 5 further including temperaturesensing means connected to said pump means providing for operationthereof only when the temperature in said chamber is above apredetermined temperature, said temperature sensing means extending intosaid chamber at a position in said path closer to said outlet thereofthan the inlet.
 9. In a vehicle, apparatus for disposing of liquid andorganic waste comprising a waste holding tank having a bottom wall,sanitizer means for vaporizing and sanitizing said waste, vehicle speedsensing means, pump means operatively associated with said speed sensingmeans for conveying waste from said tank to said sanitizer means onlywhen said sensing means senses movement of said vehicle, and conduitmeans connecting said pump to said holding tank, said conduit meansterminating in a filter member disposed in said tank at a positionspaced above said bottom wall so that agitation of liquid in said tankwill wash said filter member.
 10. Apparatus according to claim 9 whereinsaid filter member is tubular and is in a generally horizontal positionin said tank.
 11. A method of disposing of liquid and organic waste in avehicle having an engine, said method comprising the steps of: a.collecting said waste at one location on said vehicle; b. utilizing theheat from said engine to sanitize and vaporize said waste at anotherlocation on said vehicle; and c. continuously moving said waste fromsaid one to said another location only when said vehicle is moving at aspeed above a predetermined speed and when the temperature at said otherlocation is above a predetermined temperature, and retaining said wastein said one location when said vehicle is stationary or moving at aspeed below said predetermined speed.
 12. In a vehicle having an engineprovided with an exhaust system into which waste heated gases from theengine are discharged, apparatus for disposing of liquid and organicwaste comprising a holding tank for receiving said liquid and organicwaste, conduit means in communication with said holding tank and saidexhaust system, vehicle speed sensing means, temperature sensing meansfor measuring a temperature condition associated with the operation ofsaid engine, and pump means operatively associated with said speedsensing means and said temperature sensing means and located in saidconduit means for conveying waste from said holding tank to heated gasesin said exhaust system only when said speed and temperature sensingmeans sense speed and temperature conditions above predetermined minimumvalues.